[关键词]
[摘要]
为调查研究哈氏仿对虾浙江象山群体的种质资源、物种间的亲缘关系及遗传多样性状况,采用PCR扩增获得哈氏仿对虾线粒体DNA的16S rRNA和CO I基因片段,分别对其进行序列比较和系统进化分析。16S rRNA基因片段的T、C、A和G的含量分别是35.76%、19.48%、26.74%和17.88%;CO I基因片段的T、C、A和G的含量分别是35.36%、12.68%、30.54%和21.43%;A+T含量显著高于G+C含量。16S rRNA基因片段长度为558 bp,共检测出1种单倍型,没有多态性位点;CO I基因片段长度为688 bp,共检测出7种单倍型,6个多态性位点。CO I基因片段比16S rRNA基因片段变异丰富,更适于哈氏仿对虾种群的遗传多样性分析。基于16S rRNA和CO I基因片段的系统进化分析结果不太一致,结合形态学分析表明,哈氏仿对虾是仿对虾属独立的分支,与细巧仿对虾和亨氏仿对虾种类亲缘关系较近。根据CO I基因片段的遗传距离推测出仿对虾属的大致分化时间发生在中新世末期至上新世早期。
[Key word]
[Abstract]
To investigate the germplasm resources and genetic diversity of the wild population Parapenaeopsis hardwickii, 558 base of the 16S rRNA and 688 bp base of the COⅠ gene sequences were obtained from P. hardwickii wild populations by PCR amplification. T, C, A and G base content of 16S rRNA gene sequences were 35.76%, 19.48%, 26.74% and 17.88%, while COⅠ gene sequences were 35.36%, 12.68%, 30.54% and 21.43% respectively. One haplotype and no polymorphic sites were detected in 16S rRNA gene sequences, while 7 haplotypes and 6 polymorphic sites were in COⅠ gene sequences, including 5 singleton variable sites and 1 parsimony informative sites. The variations of COⅠ gene sequences were more than 16S rRNA gene sequences, showing that COⅠ gene sequences were adaptive for genetic diversity analysis in P. hardwickii. The molecular phylogentic analysis based on 16S rRNA and COⅠ gene sequences were not consistent with each other, indicating that P. hardwickii was a sole branch in the genus Parapenaeopsis, and had closer relationships with Parapenaeopsis tenella and Parapenaeopsis hungerfordi. Based on the genetic distance of COⅠ gene sequences, the differentiation time of 12 shrimp species were deduced, and the results showed that the radiation differentiation time of genus Parapenaeopsis was between the Late Miocene Epoch and the Early Pliocene Epoch.
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[基金项目]
国家科技基础条件平台项目(2016DKA30470);国家虾产业技术体系专项(CARS-47)